tranny or clutch problem?
when the truck is off i can go through the gears no problem, with the truck on, say in 1st, with my foot on the brake and the clutch all the way in it still wants to go. But with the truck on, in gear, it wont let me shift gears
It is a clutch or clutch master/slave cylinder problem. Check to see if you have a hydraulic clutch. If you do it may be out of fluid due to a leak.
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